paladin7429
Mechanical
- Aug 24, 2012
- 1
I am analyzing a 2500-psia MAWP system that is protected by a relief valve. That valve
is required by ASME Code to have no greater than 3% accumulation; in other words
the valve must be full-open at (roughly) 2575 psia. (Note: I know I am not using psig
for the conversions as I should; it is just a simplification for discussion.)
In my analyis, I assume 3% uncertainty on the lift pressure, so my "pop" is at 2575.
My question concerns how I should analyze the accumulation. Is the full-open pressure "fixed",
i.e., or should it all be adjusted (in the analysis) to 1.03*2575=2652 psia. To summarize,
the two analytical methods are:
(a) valve pops full-open at 2575 psia (the nominal full-open pressure)
(b) valve pops partially open at 2575, but does not reach full-open until 2652 psia.
I would appreciate opinions and bases, e.g., a reference.
Hope this is not too much to ask for my first thread. Thanks.
is required by ASME Code to have no greater than 3% accumulation; in other words
the valve must be full-open at (roughly) 2575 psia. (Note: I know I am not using psig
for the conversions as I should; it is just a simplification for discussion.)
In my analyis, I assume 3% uncertainty on the lift pressure, so my "pop" is at 2575.
My question concerns how I should analyze the accumulation. Is the full-open pressure "fixed",
i.e., or should it all be adjusted (in the analysis) to 1.03*2575=2652 psia. To summarize,
the two analytical methods are:
(a) valve pops full-open at 2575 psia (the nominal full-open pressure)
(b) valve pops partially open at 2575, but does not reach full-open until 2652 psia.
I would appreciate opinions and bases, e.g., a reference.
Hope this is not too much to ask for my first thread. Thanks.
